Kengate Terrazzo

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Test Data

The following information is based on experience and typical product tests carried out on pre-cast terrazzo tiles commonly manufactured and supplied by Kengate Terrazzo.  You can download this information as a Microsoft Word document at the bottom of this page.

It is not intended to be a definitive set of data, as the mix of various aggregates, colours and cement may change the characteristics of the product, but is representative of what terrazzo tiles can achieve, and is intended as a guide to the designer when choosing this product in preference to other stone and marble products.

Typical Tile Constituents

300x 300 x 28 terrazzo tile manufactured to EN13748

Typical Tile Mix (infinitely variable)

Once laid, the tiles are ground using a 40 grit wet process.

Slip Resistance Test

The test is carried out at a random selection of locations around the floor using a”4S Rubber Pendulum Device” on a clean floor. The test is carried out to a dry surface and to a wet surface. The tile mix achieved the following results over 5 locations:

The is no current minimum requirement to achieve a pass and may vary according to the client and end use requirements,

The use of a finer or coarser stone can change the slip resistance during the grinding process. A coarser stone will produce a higher slip resistance and visa-versa, however the courser the grinding process the duller the final tile finish. A highly polished tile will therefore have a lower slip resistance. The designer should consider this compromise when designing the mix. Kengate Terrazzo can advise on this aspect based on past experience of aggregate combinations.

Uniformity

Cleanability and Stain Resistance

 Tiles were applied with 3 staining agents and left in contact for 72 hours. The agents were then removed using a standard hard surface cleaner and hard bristle brush, then rinsed with clean water. A visual inspection and assessment was then carried out.

The results are as follows:

The test indicates that prolonged stains may be visible unless the staining agent is removed quickly.

The severity of the stain is however a subjective assessment and may be improved by the use of sealers.

Water Absorption

BS4131 / EN13748

Total absorption shall be no more than 8%

•  A typical result for a Kengate Products tile is 7% absorption

Strength

EN13748

No single result shall be less than 2.5N/mm2

•  A typical result for a Kengate Products tile is 5N/mm2

Weight

 A 300x300x28mm tile weighs 6.4 kg

 A Square Metre of 11 tiles therefore weighs 70kg

Co-Efficient of Thermal Expansion

The co-efficient of thermal expansion for building materials are quoted as mm per mm x 10^{-6  0}C^-1

The CTE of Concrete is 10

The CTE of Sand Cement screed is 11 to 13

The CTE of Terrazzo is 7 to 13

This is particularly relevant to choosing finishes for underfloor heating and the design of movement joints. The Tile Association have produced a study of this which is available from info@tiles.org.uk
 

Bedding

Whilst this product is not supplied or carried out by Kengate Terrazzo, the following information is provided as guidance when choosing the product.

The tiles are laid monolithically in a 3:1 sand/cement bedding which is compacted by laying the tiles and beating them into place using a soft headed hammer (usually rubber) to line and level. The bedding is effectively the adhesive for the terrazzo tiles, and is not considered to be a structural component. Any reinforcement is placed for crack control purposes only.

A good level of compaction is achieved for bedding thicknesses of up to 50mm. For thicknesses above 50mm, it is considered good practice to lay and compact an initial layer of up to 100mm, then a further layer to include the tile and up to 50mm bedding. This applies to a floor laid using a fibre reinforced bedding or D49 steel mesh.

This method should not be confused with a sand/cement screed laid and compacted by tamping and left ready for other applied finishes such as ceramic tiling, carpet, vinyl or wood finishes.

To provide an adequate specification, the following criteria should apply to a terrazzo tile floor,

The following data is from a typical terrazzo installation using Tilcon Fibre Screed to an overall depth of 150mm after laying

The following data is from a typical installation using Tilcon Screed and D49 mesh.

As a comparison, the following criteria applies to a traditional 3:1 sand/cement compacted and steel floated floor screed